I'm not on stalk book so I can't look at the pictures of your gear, but out of interest what do you have in the bottom of your mash tun?
All the points people have made a valid, and well worth considering, but fly sparging requires either a decent false bottom or a well designed manifold to get decent efficiency. If you have a simple drainage system in your tun then fly sparging isn't really the best option. Batch sparging is the way to go for your first 15-20 AG brews while you work out your system and processes and start to build consistency. Knowing your gear is important, and how different aspects contribute to efficiency is also important.
Have a listen to the brew strong podcast on mash efficiency and they give a good explanation on why the manifold design is important.
You can get good efficiency with a batch sparge, and it is what I use even after having brewed AG for 5 years or so now. I run at about 75% total efficiency, but it took me about 10 brews the really nail it all down.
Best bet is to change ONE thing at a time and see if that makes a difference. Then change something else.
JD